页面右键下拉表

<script type="text/javascript" language="javascript" >
        document.oncontextmenu=click;
        var appState = new applicationState();
        function applicationState() {
            this.contextMenu = null;
        }
        function click()
        {
            var str="";
                str="<div style='position: absolute;background-color:#48b4fc;'><table border='1'>";
                str+="<tr onmouseover='fn_set(this);'><td>111<td><tr>";
                str+="<tr onmouseover='fn_set(this);'><td>222<td><tr>";
                str+="<tr onmouseover='fn_set(this);'><td>333<td><tr>";
                str+="<tr onmouseover='fn_set(this);'><td>444<td><tr>";
                str+="</table></div>";
            if(appState.contextMenu != null) appState.contextMenu.removeNode(true)

            document.body.insertAdjacentHTML("beforeEnd", str)
            contextMenu = document.body.childNodes(document.body.childNodes.length-1)
            contextMenu.style.left = window.event.x
            contextMenu.style.top = window.event.y;
            appState.contextMenu = contextMenu
            window.event.cancelBubble = true;
            return false;
        }
        function fn_set(obj){
            obj.style.color="#24b400";
        }
        function clean() {
          var contextMenu
          if(appState.contextMenu != null) {
            contextMenu = appState.contextMenu.removeNode(true)
            contextMenu = null
          }
        }
        </script>
        <script event=onclick() for="document" type="text/javascript">clean();</script>//处理页面单击事件，关闭下拉表